Safety mechanism for stamping-presses and the like.



A. F. WALLBILLIGH.

SAFETY MECHANISM FOR STAMPING PBESSES AND THE LIKE.

APPLICATION FILED JULY 20,1913.

1,078,39 1 Patented Nov. 11, 1913.

2 SHEETS-SHEET 1.

1,078,391, Patented Nov. 11, 1913.

2 SHBETSSHEET 2.

M 27 so mumig 26 A 3/ v 32 33 33 i t VWAOMI mm a W aqmams'icsuaouh it an UNITED s'rATEs PATENT OFFICE.

ANTHONY r. WALLBHJLICH, or munonron'r, CONNECTICUT, ASSIGNOR TO THE BRYANT ELECTRIC COMPANY, OF BR'IMEPOBT, CONNECTICUT, A CORPORATION OF CONNECTICUT.

\ MECHANISM FOR STAMPING-PRESSES AND THE LIKE.

Specification of Letters Patent.

Patented Nov. '11, 1913.

Application filed July 28, 1913. Serial No. 781,646.

To all whom it may concern:

Be it known that I, ANTHONY F. WALL- BILLICH, a citizen of the United States of America, residing in the city of Bridgeport, in the county of Fairfield and State of Connecticut, have invented a certain, new and useful Improved Safety Mechanism for Stamping-Pressesand the 'like, of which the following is a specification.

My invention consists of an improved safety mechanism for stampin presses and other machines, to prevent t e operators hands or fin ers from being injured in the press in hand ing the material which is being operated on b the press.

The main 0 ject of my invention is to so construct the safety mechanism that there will be no chance for injury of the operator under any conditions of use. For this purpose I construct the mechanism so that the guard piece instead of being positively actuated, as is common, is allowed to drop by its own gravity, and interlocking means are provided such that the die control cannot be operated until the guard has'dropped all the way, and then the guard cannot be raised again until the die control devices have been restored to the normal inoperative position, with the die elevated.

In the accompanying drawing, Figure 1 is a side elevat on of my improved safety guard mechanism, with the arts in normal, inoperative position; Fig. 2 1s a similar View with the guard down in safety position, and the die control devices moved to positions where the die cannot descend onto the matrix, parts being shown in section; Fig. 3 is a plan view of the mechanism shown in Fig. 2, but detached from the frame of the press; Fi 4 is a rear view. of the same; Figs. 5 an 6 are sectional views of the valves.

My invention is designed more especially to be applied to those types of machines, in which a stamping or punching die is used under the control of a treadle or other lever, to stamp orcut pieces of metal handled by an operator who is in'control of the machine, and the purpose of the safetymechanism is to guard against the movable, die being thrown down while the operators hand is within range of the die. The construction of the press forms no part of my invention, so I have shown in the drawings only so much of the press as is necessary to an understanding of my safety guard mechanism. Thus in Figs. '1 and 2, the frame of the press is indicated at 10, the bed thereof at 11, the lower fixed die at 12 andthe u per movable die at 13. In a well known orm of press, this die 13 is actuated by an ec centric shaft normally out of action, but thrown into operation by a clutch and release mechanism, and for convenience of description it may be assumed that my invention is applied to such a press, this clutch and release mechanism being under control of what I'mafy call the control rod 14. Upon depression 0 operation to bring the upper die 13 down onto the fixed die 12.

The safety guard is a gate-like structure 15 which may be similar in general respects to guards heretofore used in stamping presses. This gate shown is in the form of an open frame pivoted freely at 16 to a supporting piece 17, which is bolted at 18 to an upright part of the frame 10 of the press. The outer side of this gate frame 15 next the operator is preferably in the form of an openwork screen, which as the frame swings 'on its pivot 16, describes an arc of a circle in the field between the operator and the dies. In its elevated position, shown in Fig. 1', the gate permits the operator to pass under the }gate and into position in the press between t e open dies the material to be operated on. In its lowered position the front edge of the guard rests upon the sur face of the bed 11, as seen in Fig. 2, so that the operator must have withdrawn his or her hands from between the dies, before the gate can drop to this lower position.

There is a rod 20, guided in an eye 21 at the side of theframe, and connected at its upper end to a lever 22 on the end of a spindle 23 turning in a partof the frame piece 17. This lever 22 has at its free end and on the side next the guard 15 a fin or 24, Fig. 3, which projects under the side piece of this guard 15, so as to support the guard in the elevated position, Fig. 1, when Fig. 1. A treadle or other lever under the control of the operator can be used to pull down the rod 20 against the spring 25, at the required moment, to cause the actuation of the rod 14 and thereby operate the clutch and release mechanism to cause the operation of the die 13. For this purpose the rod 20 or lever 22 might be connected mechanically to the control rod 14, but according to the present invention, I provide an intermediate fluid-operated means to actuate the rod 14 under the control of the lever 22, together with interlocking means, which 1 will now describe.

The spindle 23 is the spindle of a valve 26, Figs. 3 to 6, in a valve casing 27, on the frame piece 17. This valve casing has an inlet port 28 for admission of compressed air or other fluid pressure. At another oint in the casing is an exhaust port 29, Figs. 3 to 5. From the corresponding passages 30 and 31 in the valve body ports 32 and 33 in the casing lead to a cylinder 34 containing a piston 35 (Fig. 2), whose lower end 36 projects through the lower end of the cylinder and bears upon an arm 37 of the control rod 14. This latter is uided in its vertical movements by an anti riction roller 38 on the frame 10 and is normally held in its upper position Fig. 1, by a spring 39.

The ports and valve passages are so arranged that when the lever 22 is up, as seen in Fig. 1, the exhaust is open and the inlet closed. When the lever 22 is drawn down the inlet passages to the cylinder 34 are open and the exhaust is closed, but this admission of fluid pressure to the cylinder 34 can only take place after the lever 22 has been moved so far downwardly that the guard 15 has dropped all the way to the position shown in Fig. 2. To increase the safety of the device, I provide between the two levers 15 and 22, interlocking devices whereby the valve is locked from being moved far enough to open the valve, until the gate has dropped and when the valve is opened to admit pressure to operate the control rod 14, the gate is locked in the down position, Fig. 2. This is secured in a simple manner by securing to or forming on the lever 22 a locking arm 40 and on the adjacent part of the gate 15 a locking arm 41, Figs. 1 and 2, in the same vertical plane, Fig. 3. Thus so long as the gate is in the up position, the lever'22 cannot be moved to 0 en the valve, because its arm 40 will be locked by the arm 41 of the gate 15. But as soon as the gate drops to the bottom position Fig. 2, its arm 41 clears the arm 40 and the lever 22 can be drawn to the position, Fig. 2 to open the valve. Then the arm 40 will have passed u ider the arm 41, thus in turn lockin the gate 15 in the closed position, until't a lever 22 has moved back to'close the valve. When the supply valve is closed, the exhaust port is open, so that if by chance the supply is leaky, the leak willescapeto the exhaust instead of possibly operating the piston in he cylinder 34.

One important advantage of having the guard 15 drop by gravity is that it will thus not be liable to hurt the operators hands if it Should drop on them, especially if it be made of light material such as aluminium. If the guard were mechanically connected to, and operated by the control rod, it might be pulled down with such force that the gate itself would injure the operators hands if it strikes them.

I claim as my invention 1. A .safet mechanism for stamping presses and tie like, comprising a control rod for the operating mechanism of the press, a lever under the control of the operator to cause the actuation ofvthe control rod and a drop guard adaptedto he raised by said lever but to drop by its own gravity when the lever is moved.

2. A safety" mechanism for stamping presses and the like, compri'sin a control rod for the operating mechanlsm of the press, a fluid-pressure means to actuate the control rod, a lever controlling said fluid pressure means and a safety guard governed by the movement of said lever.

3. A safety mechanism for stamping presses and the like, comprisingacontrol rod for the operating mechanism of the press, a fluid-pressure means to actuate the control rod, a lever controlling said fluid pressure means and a drop guard adapted to be raised by the lever but to drop by its own gravity, when the lever is moved for the actuation of the fluid pressure means.

4. A safety mechanism for stamping presses and the like, comprising a control rod for the operating mechanism of the press, a lever under the-control of the operator to govern the actuation of the control rod, a safety guard raised by the upward movement of the lever but adapted to dro by its own gravity when the lever is lowere and a locking device whereby the lever is locked against moving the control rod while the gate is up. i i

5. A safety mechanism a... atm ag presses and the like, comprising-a-control rod for the operating mechanism of the press, a lever under control of-the operator to govern the actuation ofthe control rod, a safety guard raised by the-upward movementof the lever, but adapted to drop by its own gravity when the lever is lowered,

and interlocking devices between the guard "and lever, whereby the lever islocked against moving the control rod while'the guard is up, and the guard is locked down when the lever isin positionfor'the pressoperation.

6. A safety mechanism for stam'pin g presses and the like, comprising a control rod for the operating mechamsm of the press, a fluid pressure means to actuate the control rod, a lever controlling said fluid pressure means, a safety guard raised and o the movement of said lever and mterloc ing means between freed to be lowered b 7 press, a valve-controlled fluid pressure means to actuate the control rod, a lever to open and close the valve, a safety and freed to be lowered by saldlever and means whereby the valve is locked when the gate is up, and the gate is locked down when the valve is open.

In testimony whereof I have signed my 2 name to this specification, in the presence of two subscribing witnesses.

ANTHONY F. WALLBILLICH. Witnesses:

G, W. Goonnmon, H. M. WIGHERT.

ard raised 15 

